2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

�40 Frauke Krüger A 702 / 16:15
Seasonal and geographical dietary variation in a typical European trawling bat,
Myotis dasycneme Boie, 1825
Authors: Frauke Krüger 1 , Florian Gloza-Rausch 2 , Martin Klempt 3 , Silvia Kaschner 3 ,
Robert Sommer 1
Affiliation: 1 Department of Landscape Ecology, Institute for Natural Resource
Conservation, Christian-Albrechts-University Kiel; ²Noctalis –World of Bats
GmbH, Bad Segeberg; ³Max-Rubner-Institute, Kiel
Many bat species depend on aquatic habitats as major food supply. Of the European
Vespertilionidae at least five species can be found foraging along water bodies. The
pond bat (Myotis dasycneme Boie, 1825) is probably the largest and most adapted
European water foraging bat, strongly connected with aquatic ecosystems and
predating mainly aquatic arthropod communities. To understand the trophic strategy
of water hunting bats during reproduction, animals’ diets were studied across the
distribution range of M. dasycneme considering time related shifts. Our study
presents a detailed dietary analysis of pond bats, representing a typical trawling
Myotis species, showing a rather consistent feeding behaviour across its areal. Prey
items found in the diet of the studied bat represent as well trawling behaviour as
aerial hawking. Pond bats seem to feed mainly on Chironomidae adults and subadults,
especially during lactation, but shift predation towards other prey items, e.g.
Lepidoptera, around the time of weaning. Additionally they also seem to feed
regularly on fish during gravity and lactation, only shown by molecular dietary
analyses. Whether Pond bats are “scavengers” feeding opportunistically on
everything available on water surfaces or if they select for certain prey groups is
being discussed.
�41 Tamara Pokorny A 702 / 16:30
Long distance dispersal of male orchid bees across the Yucatán peninsula
Authors: Tamara Pokorny 1 , Nils Blumreiter 1 , Javier Quezada-Euan 1 , Thomas Eltz 1
Affiliation: 1 Ruhr-Universität Bochum, Department for Animal Ecology, Evolution, and
Biodiversity
A characteristic trait of male orchid bees (Apidae, Euglossini) is the collection of
volatile chemicals (fragrances) from the environment, which are stored in specialized
hind leg pockets for later exposure during pre-mating behavior. The search for
volatiles may lead to large foraging ranges or even an entirely nomadic life style in
males, and the very low population genetic structure observed in orchid bees is in
agreement with either notion. Flight distances of a few kilometers have been
demonstrated previously by classical mark-recapture and radiotelemetry. Here, we
applied two novel mark-recapture techniques for assessing flight distances of male
euglossines on the Yucatán peninsula, a large area of rather uniform vegetation and
topography in southern Mexico. Bees were marked manually with lasting scratch
patterns on the thorax cuticle, or marked themselves chemically by collecting from
fragrance baits intermixed with distinct and not naturally occurring substances. Over
the course of three weeks, bees were captured along transects across Yucatán and
checked for scratch marks or marker substances (laboratory analyses using GC/MS).
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